Intumescent composition

ABSTRACT

Non-flaming intumescent compositions are obtained by mixing a normally self-extinguishing intumescent agent with a haloorganophosphorus compound, e.g., a phosphate, thiophosphate, phosphonate, phosphonite, phosphinite, phosphite, thiophosphite, tertiary phosphine, phosphine oxide, or phosphine sulfide. Among the preferred haloorganophosphorus compounds are halohydrocarbon phosphates, such as tris(2,3-dibromopropyl)phosphate, tris(2,3dichloropropyl)phosphate, tris(tribromophenyl)phosphate, etc.

Uited States atent Green et al.

1 Dec. 17, 1974 INTUMESCENT COMPOSITION Inventors: Joseph Green, East Brunswick;

Shirley H. Roth, Highland Park, both of NJ.

Assignee: Cities Service Company, New York,

Filed: Apr. 17, 1972 Appl. No.: 244,959

US. Cl. 252/8.l, 106/15 FP, 117/136 Int. Cl C09d 5/18 Field of Search 252/8.1; 117/136;

References Cited UNITED STATES PATENTS 9/1971 DiPietro 252/8.1

3,668,302 6/1972 Boland 252/8.l X

Primary ExaminerMayer Weinblatt Attorney, Agent, or Firm-Patricia J. Hogan [57] ABSTRACT 12 Claims, N0 Drawings INTUMESCENT COMPOSITION BACKGROUND OF THE INVENTION 1. Field of the Invention ll ll 11 H N 6: Ar X Ar g N 2 O O This invention relates to intumescent compositions h i A i a di l ti id d X i a diand more particularly relates to non-flaming intumescent compositions containing a normally selfextinguishing intumescent agent.

2. Description of the Prior Art It is known that a substrate may be protected from heat and fire by the application of an intumescent composition. Intumescent compositions of the prior art usually contain an intumescent agent having at least three components, i.e., a carbonific, a spumific, and a catalyst; and they are typically characterized by the disadvantages of high cost, low spreading rate, relatively poor efficiency, poor water resistance, and poor weatherability.

As disclosed in US. Pat. No. 3,535,130, it has been discovered that a one-component intumescent agent has advantages over multicomponent intumescent agents. However, the intumescent agents of the patent have poor adherence to substrates and have an undesirable degree of moisture sensitivity.

Improved one-component intumescent agents having good efficiency, a low level of moisture sensitivity, and good adherence to substrates are disclosed in copending applications Ser. Nos. 196,229, filedNov. 5, 1971; 211,635, filed Dec. 23, 1971; 219,875, filed Jan. 21, 1972; 225,638, 225,639, 225,660, 225,661, and 225,650, filed Feb. 11, 1972; 228,381, 228,382, 228,383, and 228,384, filed Feb. 22, 1972; and 230,101, 230,133, 230,134, 230,135, and 230,136, filed Feb. 28, 1972, all in the name of Shirley I-I. Roth; and 21 1,636, filed Dec. 23,1971, in the names of Shirley H. Roth and Joseph Green. These new intumescent agents are satisfactory for most applications, but many of them intumesce with a slight self-extinguishing flame which makes them less desirable for applications having very stringent requirements. It would therefore be desirable to render these normally self-extinguishing compounds non-flaming.

SUMMARY OF THE INVENTION An object of this invention is to provide novel intumescent compositions.

Another object is to render normally extinguishing intumescent agents non-flaming.

These and other objects are attained by mixing a normally self-extinguishing intumescent agent with a haloorganophosphorus compound.

self- DESCRIPTION OF THE PREFERRED EMBODIMENTS valent functional group, as taught in the aforementioned copending application Ser. No. 196,229, (B) self-extinguishing compounds corresponding to the formula:

RHN Ar S Z 0 wherein Ar is a divalent aromatic. residue; R and R are hydrogen or a hydrocarbon, halohydrocarbon, or acyl radical;Zis-O-,S

Ar NHR' or R" in which R" is an alkylene radical containing 1-5 car'- bon atoms; and n is 0 or 1, as taught in the aforementioned copending application Ser. No. 21 1,635, (C) self-extinguishing compounds corresponding to the formula:

RHN Ar NH wherein Ar is a divalent aromatic residue and R is hydrogen or a hydrocarbon, halohydrocarbon, or acyl radical, as taught in the aforementioned copending application Ser. No. 221,636, (D) self-extinguishing compounds corresponding to the formula:

' II I H mm A1" s.- N c N11,) s

wherein Ar' is a divalent aromatic residue, R is hydrogen or a hydrocarbon, halohydrocarbon, oracyl radical, and X is oxygen or sulfur, as taught in the aforementioned copending application Ser. No. 219,875, (E) self-extinguishing compoundscorresponding to the formula: V

and (F) self-extinguishing compounds corresponding to the formula:

0 R RIIN-Ar-Q-IG-JI wherein Ar is a divalent aromatic residue, R is a substituted or unsubstituted pyridyl, pyrimidyl, pyrazyl, thiazolyl, isothiazolyl, oxazolyl, isoxazolyl, or triazolyl radical, and R is hydrogen, hydrocarbon, substituted hydrocarbon, or acyl, as taught in the aforementioned copending applications Ser. Nos. 230,134, 230,135, 230,136, 230,133, and 230,101. The teachings of these copending applications are incorporated herein by reference.

More specific examples of normally selfextinguishing intumescent agents which may be rendered nonflaming in accordance with the present invention are the o,o'-, m,m,'-, and p,p'-oxybis(benzenesulfonamides bis( p-aminophenyl )sulfone, l ,2- (4-acetamidophenylsulfonyl)ethane, sulfanilamide, pacetamidobenzenesulfonamide, paminobenzenesulfonylurea, p-aminobenzenesulfonylthiourea, 2-sulfanilamidopyridine, 3- sulfanilamidopyridine, 4-sulfanilamidopyridine, 2- sulfanilamidopyrimidine, 4-sulfanilamidopyrimidine, -sulfanilamidopyrimidine, 3-sulfanilamidopyridazine, 2-sulfanilamidopyrazine, 2- sulfanilamidobenzopyrazine, 3-sulfanilamidopyrazole, Z-sulfanilamidoimidazole, 3-methyl- 1 -phenyl-5- sulfanilamidopyrazole, 2-phenyl-3- sulfanilamidopyrazole, 2-sulfanilamido-1,3,4-thiazole, 5-methyl-2-sulfanilamido-l ,3,4-thiadiazole, 5-ethyl-2- sulfanilamido-l ,3 ,4-thiadiazole, 5-methyl-3- sulfanilamido-l ,2,4-oxadiazole, 4-phenyl-3- sulfanilamido-l ,2,5-oxadiazole, 2- sulfanilamidothiazole, 2-sulfanilamido-4- methylthiazole, 5-sulfanilamido-3-methylisothiazole, 2-sulfanilamido-4,5-dimethyloxazole, 3-sulfanilamido- S-methylisoxazole, l-sulfanilamidol ,2,3-triazole, 3- sulfanilamidol ,2,4-triazole, 4-sulfanilamidol ,2,4- triazole, sulfanilamidobenzene, N -2- pyridylsulfanilamide, N -2-quinolylsulfanilamide, N -2- pyrimidylsulfanilamide, N -5-pyrimidylsulfanilamide, N -2- pyrazylsulfanilamide, N -2-thiazolylsulfanilamide, N"- 1,2,4-triazol-3-ylsulfanilamide, etc.

The haloorganophosphorus compound which is mixed with the normally self-extinguishing intumescent agent may be any of a variety of types of haloorganophosphorus compounds (i.e., organophosphorus compounds having one or more halogens attached to an organic radical), e.g., a phosphate, thiophosphate, phosphonate, phosphonite, phosphinite, phosphite, thiophosphite, tertiary phosphine, phosphine oxide, phosphine sulfide, etc. It may be aliphatic or aromatic, and it usually contains about 325% P, about 575% halogen such as Cl and/or Br, about -75% C, about 0.58% H, and about 0-40% 0 and/or S, based on the weight of the compound. It is preferably a waterinsoluble compound.

Exemplary of suitable haloorganophosphorus compounds are tris(bromochloropropyl )phosphate, tris( 2chloroethyl )phosphate, tris( ochlorophenyl)phosphate, tris(2,3-

dibromopropyl )phosphate, tris( l ,2-dichloroethyl)- phosphate, tris( l,3-dichloroisopropyl)phosphate, tris(- 2,3-dichloropropyl)phosphate, tris(tribromophenyl)- phosphate, allyl chloroethyl v phosphate, bis(2,3- dibromopropyl)phosphate, 3-bromopropyl phosphate, tris(4 -chlorophenyl)thiophosphate, diethyl 2-bromoethylphosphonate, bis(tribromoethyl)phenylphosphonite, 2-chloroethyl diphenylphosphinite, tris(2,2,2- trichloroethyl )phosphite, tris( bromolauryl )trithiophosphite, tris(chloromethyl)phosphine, 4- bromophenyl diethyl phosphine, tris(chloromethyl)- phosphine oxide, tris(2-chlorophenyl)phosphine oxide, bis(4-methylphenyl)4-chlorophenyl phosphine sulfide,

N-4-pyrimidylsulfanilamide,

etc., and mixtures thereof. The preferred haloorganophosphorus compounds are the halohydrocarbon phosphates.

The haloorganophosphorus compound is mixed with the normally self-extinguishing intumescent agent in any suitable manner, e.g., by grinding the ingredients together, to provide an admixture containing about 0.5-% preferably about 5-100%, of phosphorus compound, based on the weight of the intumescent agent. Smaller amounts of phosphorus compound are usually inadequate to render the intumescent agents non-flaming; larger amounts generally decrease the degree of intumescence too much. Ordinarily the less efficient phosphorus compounds are used in concentrations toward the upper end of the aforementioned range, while the more efficient phosphorus compounds are used in the lower concentrations.

For use in protecting a substrate from heat and fire, the non-flaming intumescent agent/phosphorus compound compositions of the invention may be applied in any suitable manner, e.g., electrodeposition, spraying of powdered intumescent agent/phosphorus compound composition onto an adhesive substrate, etc. However, it is usually preferred to compound the intumescent agent and phosphorus compound with a binder, e.g., nitrocellulose, and optionally also with one or more of the other ingredients conventionally. used in intumescent compositions, e.g., stabilizers, dispersing agents, pigments, driers, biocides, antifoamers, thickeners, protective colloids, fillers, blowing agents, etc.; disperse the composition in a suitable liquid medium, e.g., water or a solvent or solvent mixture; and apply the coating composition thus formed to the substrate to be protected. As is the case with conventional intumescent coating compositions, it is frequently convenient to apply these coating compositions in the form of a paint having a solids content of about 10-70% by weight and an intumescent agent-phosphorus compound/binder weight ratio of about 0.075-14/l to deposit a coating having a dry thickness of about 0.00l-O.75 inch,

The intumescant agents of the invention are eflicient, have low moisture sensitivity, and intumesce without flaming to form foams having good volume, cell structure, and adherence to substrates, such as wood, metal,

and plastics. They are also useful as flame retardants in normally flammable compositions.

The following examples are given to illustrate the invention and are not intended as a limitation thereof. Unless otherwise specified, quantities mentioned are quantities by weight.

EXAMPLE I CONTROL Place 1 gram of sulfanilamide in an aluminum pan and flame it with a propane torch. The compound intumesces with a slight self-extinguishing flame to form an excellent volume of foamhaving a good cell structure.

EXAMPLE ll Repeat Example 1 except for intimately mixing one part of the sulfanilamide with 0.25 part of tris(2,3- dibromopropyl) phosphate before applying the propane torch. The mixture intumesces without flaming to form a good but lesser volume of foam having a good cell structure.

EXAMPLE III CONTROL Place one gram of p,p'-oxybis(benzenesulfonamide) in an aluminum pan and flame it with a propane torch. The compound intumesces with a slight selfextinguishing flame to form an excellent volume of foam having a good cell structure.

EXAMPLE IV Repeat Example III except for intimately mixing one part of the p,p'-oxybis(benzenesulfonamide) with 0.5 part of tris(2,3-dichloropropyl)phosphate before applying the propane torch. The mixture intumesces without flaming to form a foam having a volume and cell structure comparable to the foam of Example III.

EXAMPLE V Repeat Example III except for intimately mixing one part of the p,p'-oxybis(benzenesulfonamide) with 0.15 part of tris(tribromophenyl)phosphate before applying the propane torch. The mixture intumesces without flaming to form a good but lesser volume of foam having a good cell structure.

Similar results are observed when tris(bromochloropropyl )phosphate and the other haloorganophosphorus compounds and self-extinguishing agents mentioned in the formula:

9 Q H N -Ar-X-Ar- NH O 0 wherein Ar is a divalent aromatic residue and X is a divalent functional group,

2. self-extinguishing compounds corresponding to the formula:

wherein Ar is a divalent aromatic residue; R and R are hydrogen or a hydrocarbon, halohydrocarbon, or acyl radical; Z is O S or in which R" is an alkylene radical containing 1-5 carbon atoms; and n is 0 or 1,

3. self-extinguishing compounds corresponding to the formula:

9 RHN-Ar -NH wherein Ar is a divalent aromatic residue and R is hydrogen or a hydrocarbon, halohydrocarbon, or acyl radical,

4. self-extinguishing compounds corresponding to theformula:

Q H X RHN-Ar-s-N-c-Nn wherein .Ar is a divalent aromatic residue, R is hydrogen or a hydrocarbon, halohydrocarbon, or acyl radical, and X is oxygen or sulfur,

5. self-extinguishing compounds corresponding to theformula:

Q t R N-Ar-s-N-R" wherein Ar is a divalent aromatic residue; R is hydrogen, hydrocarbon, halohydrocarbon, or acyl; and R" is a substituted or unsubstituted pyridyl, pyrimidyl, pyridazyl, pyrazyl, pyrazolyl, imidazolyl, thiadiazolyl, oxadiazolyl, thiazolyl, isothiazolyl, oxazolyl, isoxazolyl, triazolyl, or aromatichydrocarbon radical, and

6. self-extinguishing compounds corresponding to theformula:

Q R RHN-Ar-N -H 3. The composition of claim 1 wherein the haloorganophosphorus compound is a halohydrocarbon phosphate. I

4. The composition of claim 3 wherein the halohydrocarbon phosphate is tris(2,3- dichloropropyl )phosphate;

5. The composition of claim 3 wherein the halohydrocarbon phosphate is tris(2,3- dibromopropyl)phosphate.

6. The composition of claim 3 wherein the halohydrocarbon phosphate is tris(bromochloropropyl)phosphate.

7. The composition on claim 3 wherein the halohydrocarbon phosphate is tris(tribromophenyUphosphate.

8. The composition of claim 1 wherein the intumescent agent is bis(p-aminophenyl)sulfone.

9. The composition of claim 1 wherein the intumescent agent is l,2-bis(4-acetamidophenylsulfonyl)ethane.

10. The composition of claim 1 wherein the intumescent agent is sulfanilamide.

11. The composition of claim 1 wherein the intumescent agent is p-acetamidobenzenesulfonamide.

12. The composition of claim 1 wherein the intumescent agent is p,p-oxybis(benzenesulfonamide). 

1. A NON-FLAMING INTUMESCENT COMPOSITION CONSISTING ESSENTIALLY OF: A. A NORMALLY SELF-EXTINGUISHING INTUMESCENT AGENT SELECTED FROM THE GROUP CONSISTING OF:
 1. SELF-EXTINGUISHING COMPOUNDS CORRESPONDING TO THE FORMULA:
 2. SELF-EXTINGUISHING COMPOUNDS CORRESPONDING TO THE FORMULA:
 2. The composition of claim 1 wherein the concentration of haloorganophosphorus compound is about 5-150%, based on the weight of the intumescent agent.
 2. self-extinguishing compounds corresponding to the formula:
 3. self-extinguishing compounds corresponding to the formula:
 3. The composition of claim 1 wherein the haloorganophosphorus compound is a halohydrocarbon phosphate.
 3. SELF-EXTINGUISHING COMPOUNDS CORRESPONDING TO THE FORMULA:
 4. SELF-EXTINGUISHING COMPOUNDS CORRESPONDING TO THE FORMULA:
 4. The composition of claim 3 wherein the halohydrocarbon phosphate is tris(2,3-dichloropropyl)phosphate.
 4. self-extinguishing compounds corresponding to the formula:
 5. self-extinguishing compounds corresponding to the formula:
 5. The composition of claim 3 wherein the halohydrocarbon phosphate is tris(2,3-dibromopropyl)phosphate.
 5. SELF-EXTINGUISHING COMPOUNDS CORRESPONDING TO THE FORMULA:
 6. SELF-EXTINGUISHING COMPOUNDS CORRESPONDING TO THE FORMULA:
 6. The composition of claim 3 wherein the halohydrocarbon phosphate is tris(bromochloropropyl)phosphate.
 6. self-extinguishing compounds corresponding to the formula:
 7. The composition on claim 3 wherein the halohydrocarbon phosphate is tris(tribromophenyl)phosphate.
 8. The composition of claim 1 wherein the intumescent agent is bis(p-aminophenyl)sulfone.
 9. The composition of claim 1 wherein the intumescent agent is 1,2-bis(4-acetamidophenylsulfonyl)ethane.
 10. The composition of claim 1 wherein the intumescent agent is sulfanilamide.
 11. The composition of claim 1 wherein the intumescent agent is p-acetamidobenzenesulfonamide.
 12. The composition of claim 1 wherein the intumescent agent is p,p''-oxybis(benzenesulfonamide). 